Squamous Cell Carcinoma Figure 2

Figure 2: Squamous cell carcinoma at base of the ear involving Zymbal’s gland (Ramekin).
Case history and photos


Ramekin, a 22-month-old male rat, presented with a large lump on his face just below the right ear.

Clinical Signs

The lump appeared virtually overnight, growing to a diameter of around 1/2 inch. It was believed, at that time, to be an abscess. His general condition was otherwise healthy.

Initial Exam

Physical examination by the vet revealed a very hard lump that didn’t move freely. Upon X-ray, no bone involvement or other features were apparent. Needle aspiration was performed and serosanguinous fluid obtained showing mostly red blood cells, macrophages (cells that have the ability to ingest and destroy particulate substances, such as bacteria) and some seg neutrophils (segmented white blood cell).


Possible cyst.

Possible tumor formation.


Treatment was initially begun by having the cyst drained, and starting a course of enrofloxacin (Baytril), and Cortisone (dexamethasone).

A few days following the initial treatment, the cyst again returned, and drainage was repeated.

DSMO was prescribed, and applied daily to the area of cyst removal. The cyst reappeared after two days.


At this time a recurrent hydrocyst due to trauma to the face, or Zymbal’s gland tumor possibly squamous cell in nature was suspected and the decision made to do surgery.

Exploratory surgery was performed:

“The cyst explored, was invasive of muscle, nerves, and blood vessels around the ear base. Invaded ear brought up pus and blood. The area was debrided and flushed. As much of the tissue was curretted as possible. A drain inserted in place, too leave for 5 days if possible.”


The cyst returned within 3 days post op. It was now filling with fluid rapidly and drainage could be seen coming from the ear canal and incision drain. The tumor itself was visibly growing larger and rapidly below the cyst.
Daily draining of the cyst was performed for several days and during this time Ramekin continued to be otherwise active and eating.

One week after surgery the tumor/cyst hemorrhaged profuse bright red blood from the ear canal, the surgical incision, and the opening made for the drain that had been inserted in the cyst. The decision was made that Ramekin not be allowed to suffer, and was euthanized the following day.


Ramekin, The Bear
Photo 1: Depicts developing growth noticed here on side of face.
  Ramekin, The Bear
Photo 2: Closer camera view of growth.
  Ramekin, The Bear
Photo 3: Tumor development can be clearly seen using the ear and eye as a marker.

Photos courtesy of Al and Robyn Arthur, of The Dapper Rat, http://www.dapper.com.au
Collaborated case study by, Dr Larissa Ladyko B.V.Sc, and Robyn Arthur.

Diagram drawing of Zymbal’s gland location in rats https://reni.item.fraunhofer.de/reni/trimming/manus.php?mno=034.


Linked from


The Rat Guide and its affiliates accept no responsibility for misuse or misunderstanding of its information. This guide in whole or part, exists solely for the purpose of recognizing and understanding the care and illnesses in the pet rat. Please seek advice and treatment from a qualified Veterinarian if your rat is ill.

2000 - 2023 by Karen Grant RN. All rights reserved.
All other written and visual materials used by permission of specific authors for the sole use of the Rat Guide. Please visit our Privacy Policy for details.
Brought to you by KuddlyKorner4u
See Logos page for linking to the Rat Guide.
Contact us here: Rat Guide Team
Please note: Rat Guide email is not checked daily. Send e-mail to if you have an urgent medical problem with your pet rat. When possible, it is always best to take your rat to a qualified rat veterinarian.